fixed examples' CMakeLists: not all examples were build

had a if/else condition wrong concerning the availability test of
ViennaDeviceCollection -> fixed now
ensuring that the damping for the nonlinear poisson-dd problem is not >0.5

see: https://github.com/viennafvm/viennafvm-dev/commit/3144e05af36be3beb02ee9be85d6d07c34031395

also removed whitespaces
removed trailing whitespaces in all source files
fixed poisson_dd-np: limiting damping to 0.9 - mosfet and nin2d work
removed gcc 4.8.1 warnings
NP diode 2d template: ready and working, also added svg/png picture
removed daping config from examples+started working on postprocessing

currently in the middle of implementing E and J computation